A Kurdish peshmerga fighter patrols near the Mosul Dam at the town of Chamibarakat outside Mosul, Iraq, on Aug. 17. / AP

by Jim Michaels, USA TODAY

by Jim Michaels, USA TODAY

BAGHDAD - Iraqi forces were consolidating gains around the Mosul Dam on Monday, after a ground offensive supported by nearly three dozen American airstrikes pushed Islamic State militants off the dam after several days of fighting, Iraqi officials said.

The claim amounts to a significant victory for Iraq's government, which has struggled to blunt the momentum of the militants.

The U.S. military said it launched 15 airstrikes Monday in support of the offensive to retake the dam, one of the most critical structures in Iraq. It controls the supply of water for much of the country and its destruction would cause massive flooding of nearby cities.

In total, the U.S. military conducted 35 airstrikes in support of Iraqi forces near the dam, about half of the total number of U.S. airstrikes since the mission began Aug. 8, according to U.S. Central Command.

"The Iraqi flag is flying on top of the dam," said Sabah al-Nuaman, a spokesman for Iraq's counterterrorism force.

Iraq's military said it was still trying to retake areas around the dam, which would prevent militants from attempting to counterattack. The Iraqi forces are also continuing to clear buildings around the dam.

Lt. Gen. Qassim Atta, a spokesman for the Iraqi military, said significant amounts of weapons were captured from the militants, though he did not specify how many. Between 800 and 900 militants were occupying the dam area, al-Nuaman said. "A lot were killed," he said.

Militants seeded the area around the dam with roadside bombs and booby traps, making progress slow for Iraqi forces. About 170 improvised explosives were found by ground forces, according to al-Nuaman.

The Iraqi military said the dam itself was not rigged with explosives. Al-Nuaman speculated that the fighters had not had time to damage the facility before Iraqi forces attacked.

The American strikes in support of the Mosul Dam offensive represent an expansion of the U.S. mission, which was initially designed to prevent militants from overrunning Irbil, the capital of the Kurdish region, and to save members of the Yazidi religious sect who were trapped by the thousands on a mountain to escape the Islamic State militants.

The air campaign around the dam has allowed Kurdish forces to begin retaking territory seized by the militants, originally known as the Islamic State of Iraq and the Levant (ISIL) and the Islamic State of Iraq and Syria (ISIS). The group, which became battle-hardened during three years fighting against the government regime in Syria, has shortened its name to the Islamic State.

President Obama sent a letter to Congress on Sunday explaining his authorization of the latest strikes.

"The failure of the Mosul Dam could threaten the lives of large numbers of civilians, endanger U.S. personnel and facilities, including the U.S. Embassy in Baghdad, and prevent the Iraqi government from providing critical services to the Iraqi populace," Obama said in the letter.

Obama emphasized that the mission is limited in "scope and duration."

IS militants seized the dam this month, gaining control over electricity distributed to northern Iraq and the capability to flood Mosul, Iraq's second-largest city.

The U.S. military used a mix of aircraft and drones in Monday's strikes, destroying or damaging nine militant fighting positions, a checkpoint, six armed vehicles, a light-armored vehicle, a vehicle-mounted anti-aircraft artillery gun and an improvised explosive emplacement belt, according to U.S. Central Command.

The militants captured an array of U.S. military equipment from Iraqi forces in June when four divisions collapsed in Mosul after the radical forces attacked the city. The equipment gave Islamic State fighters an advantage in firepower, but they're vulnerable to attack from the air.